Chi Cheuk Tsang

Office: 1087 Evans
E-mail: chicheuk at math.berkeley.edu

I am a fifth year PhD student in the UC Berkeley math department. I am interested in low-dimensional topology. More specifically, I like thinking about 3-manifolds, their geometry, and flows and foliations on them.

My advisor is Ian Agol.

Starting in Fall 2023, I will be a postdoc at the Centre de recherches mathématiques.

I received my BSc in mathematics from Chinese University of Hong Kong in 2018.

I am coorganizing the student 3-manifold seminar with Eduardo Reyes in Spring 2023.

Here is my CV.

Teaching

Research

Chi Cheuk Tsang; "On the set of normalized dilatations of fully punctured pseudo-Anosov maps", In preparation
Michael Landry and Chi Cheuk Tsang; "Endperiodic maps, splitting sequences, and branched surfaces", Preprint (2023). arXiv:2304.14481
Eriko Hironaka and Chi Cheuk Tsang; "Standardly embedded train tracks and pseudo-Anosov maps with minimum expansion factor", Preprint (2022). arXiv:2210.13418
Chi Cheuk Tsang; "Constructing Birkhoff sections for pseudo-Anosov flows with controlled complexity", Preprint (2022). arXiv:2206.09586
Chi Cheuk Tsang; "Veering branched surfaces, surgeries, and geodesic flows", Preprint (2022). arXiv:2203.02874
Ian Agol and Chi Cheuk Tsang; "Dynamics of veering triangulations: infinitesimal components of their flow graphs and applications", Algebraic and Geometric Topology, to appear. arXiv:2201.02706
Ki Fung Chan, Spiro Karigiannis, and Chi Cheuk Tsang; "The L_B-cohomology on compact torsion-free G₂ manifolds and an application to "almost" formality"; Annals of Global Analysis and Geometry 55 (2019), 325-369. DOI: doi.org/10.1007/s10455-018-9629-x
Ki Fung Chan, Spiro Karigiannis, and Chi Cheuk Tsang; "Cohomologies on almost complex manifolds and the ∂∂-lemma"; Asian Journal of Mathematics 23 (2019), 561-584. DOI: doi.org/10.4310/AJM.2019.v23.n4.a2

Selected talks:

Veering triangulations and Birkhoff sections @ 13 Apr 2023, Anosov dynamics, CIRM
Dilatations of pseudo-Anosov maps and standardly embedded train tracks @ 20 Feb 2023, University of Wisconsin Dynamics Seminar
Fibrations, depth 1 foliations, and branched surfaces @ 3 Feb 2023, Caltech Geometry & Topology Seminar
Markov partitions for geodesic flows @ 26 Apr 2022, Yale Geometry and Topology seminar
Veering triangulations and pseudo-Anosov flows @ 3 Mar 2022, Geometric Topology Grad and Postdoc Seminar, Online
Veering branched surfaces @ 10 Apr 2021, GSTGC 2021, Online (Indiana University)
Introduction to pseudo-Anosov flows, Markov partitions, and dynamic pairs @ 2 & 16 Oct 2020, 3-manifold seminar, UC Berkeley

Postcards that I made for NCNGT 2021 and NCNGT 2022.

Some computational resources:

Census of veering triangulations; up to triangulations with 16 tetrahedra
Veering; GitHub repository of Python code for working with veering triangulations.
KnotFolio; online tool for identifying knots from drawings, by Kyle Miller
KnotInfo; database for knots (of ≤ 12 crossings) and their invariants
The CompuTop.org Software Archive; list of software useful for studying low-dimensional topology

Some figures from drafts of papers and other random math sketches.

Qual resources

The syllabus and transcript for my qualifying exam.

I worked through some textbook exercises when preparing for my quals. Here are some hand-written solutions to problems I found interesting. The first page of each pdf records which questions are included. Disclaimer: I do not guarantee correctness of the solutions.